1. Field of the Invention
The present invention relates to a structure of a rotor of a superconductive generator. More particularly, it relates to a rotor in which a connecting part between a damper and a torque tube has excellent mechanical strength and is not adversely affected by heat shrinkage.
2. Description of the Prior Art
FIG. 1 shows a conventional rotor of a superconductive generator.
In FIG. 1, a torque tube (1) is placed to be surrounded by a damper (2) and a superconductive coil (3) is placed inside of the torque tube (1). The superconductive coil (3) is held at a central zone of the torque tube (1). The shaft (4) of the rotor is held by a bearing (5). One end of the torque tube (1) is formed in one piece with the damper (2) and the shaft (4) and the other end of the torque tube (1) is connected through a movable part (6) to the end of the damper (2).
The damper (2) is also used as a vacuum vessel.
When the superconductive coil (3) placed in the torque tube (1) in the rotor of the superconductive generator having said structure is cooled to a cryogenic temperature of about -269.degree. C., the electric resistance becomes zero and the excitation loss is eliminated and the stong magnetic field is generated by the superconductive coil (3) and the AC power is generated from a stator (not shown).
Thus, a flexible movable part (6) is formed between the torque tube (1) and the damper (2) to prevent the affect caused by the heat shrinkage. The torque tube (1) is cooled to a cryogenic temperature together with the superconductive coil (3) and accordingly, the heat shrinkage of the torque tube is caused whereby certain discrepancy is caused to the damper (2) formed in one piece with the torque tube (1) by the heat shrinkage. In order to prevent the affect of the heat shrinkage, the movable part (6) is formed between the end of the torque tube (1) and the damper (2).
There is the other conventional feature shown in FIG. 2 wherein a movable part (6) is formed at one end of the damper (2) so as to prevent the discrepancy caused by the heat shrinkage between the torque tube (1) and the damper (2).
In the conventional rotor of the superconductive generator, the adverse affect caused by the heat shrinkage can be prevented by the movable part (6). On the contrary, the movable part is mechanically brittle. Thus, the dangerous speed of the rotor may be too low or the vibration caused by the rotation may be severe. Further more, the structure of the movable part (6) is complicated not to be easily assembled.